The aim of this research is to understand how changes in lipid structure and composition effect facilitated glucose transport. The naturally occurring phospholipids of the plasma membrane of LM cells with reduced sterol levels will be exchanged for either fully saturated or unsaturated phospholipids to determine whether the transporter is sensitive to the bulk properties of the membrane lipids. The partially purified transporter from LM cells will be reconstituted with various phospholipid mixtures to document specific lipid requirements both with regard to head group and acyl group phospholipid structure. Finally the glucose transporter from red blood cells will be isolated and both reconstitution and membrane fusion will be employed to begin documenting the effects of lipid composition and structure on this transport system.